Dust boot, method of manufacturing dust boot, and shock absorber

Abstract

A dust boot includes a tubular boot body and an annular flange portion linked to an upper end of the boot body. In an outer side of the flange portion, an angle between the flange portion and a line perpendicular to an axis of the boot body is set to be larger than 0° and smaller than 90°.

The invention claimed is: 
     
       1. A method of manufacturing a dust boot for a shock absorber, the shock absorber comprising:
 a cylinder; 
 a rod configured to move into and out of the cylinder; 
 a rod-side spring seat installed in the rod; 
 a cylinder-side spring seat installed in the cylinder; 
 a suspension spring interposed between the rod-side spring seat and the cylinder-side spring seat; and 
 the dust boot, 
 wherein the dust boot has
 a tubular boot body provided with an extendable/contractible bellows portion to cover the rod, and 
 an annular flange portion linked to an upper end of the boot body and held between the rod-side spring seat and the suspension spring, 
 
 wherein the shock absorber further comprises a rubber seat installed in an upper end of the suspension spring and interposed between the flange portion and the suspension spring, and 
 wherein an angle between the flange portion and a line perpendicular to an axis of the boot body in an outer side of the flange portion is set to be larger than 0 degrees and smaller than 90 degrees, 
 said method comprising:
 forming both the boot body and the flange portion through blow molding. 
 
 
     
     
       2. The method of  claim 1 , the method comprising:
 inserting a tubular resin material into a mold for integrally molding the boot body and the flange portion; and 
 blowing gas into the resin material to press the resin material to the mold in order to form the dust boot. 
 
     
     
       3. The method of  claim 1 , wherein
 the angle is set to 30 degrees or larger and 60 degrees or smaller. 
 
     
     
       4. A shock absorber, comprising:
 a cylinder; 
 a rod configured to move into and out of the cylinder; 
 a rod-side spring seat installed in the rod; 
 a cylinder-side spring seat installed in the cylinder; 
 a suspension spring interposed between the rod-side spring seat and the cylinder-side spring seat; and 
 a dust boot,
 wherein the dust boot has
 a tubular boot body provided with an extendable/contractible bellows portion to cover the rod, and 
 an annular flange portion linked to an upper end of the boot body and held between the rod-side spring seat and the suspension spring, 
 
 wherein an angle between the flange portion and a line perpendicular to an axis of the boot body in an outer side of the flange portion is set to be larger than 0 degrees and smaller than 90 degrees, and 
 wherein the shock absorber further comprises a rubber seat installed in an upper end of the suspension spring and interposed between the flange portion and the suspension spring. 
 
 
     
     
       5. The shock absorber according to  claim 4 , wherein
 the boot body has a cutaway hole, and 
 the rubber seat has a protrusion fitted to the cutaway hole.